2002 Toyota Tacoma low beams quit working, door locks won't work, no radio, no cruise control what could be the problem? Have checked the fuses and there doesn't appear to be a problem with them. Someone said the ECM could that be it?

  • ECM is unlikely, BCM maybe. Check engine light on?
    – Ben
    Jul 6 '16 at 12:54
  • 1
    Very unlikely that it's the ECM - that only controls engine issues and (on some vehicles) security. Check for good earths - especially with so many unrelated electrical issues, that's where I'd be looking first.
    – PeteCon
    Jul 6 '16 at 14:48
  • Time for a schematic and a test light. It is likely one common wire that has caused issues. Start with once circuit and trace it out. Find out where you are getting voltage and where you aren't.
    – rpmerf
    Jul 6 '16 at 20:12
  • No check engine light
    – Des
    Jul 10 '16 at 21:54

After looking at a ground distribution diagram the cruise, head lights and power door locks share some things in common. Given that some things I assume work and others that obviously don't, it would be isolated to a single branch of the circuit. Unfortunately these splices are located in the dash and the dash may need to be removed or pulled back to gain access.

enter image description here

ID, IG is the ground to chassis you'd want to look at. And J/B 3 would be the next place to look.

An easy place to check the cruise control system would be at the cruise control computer in the right kick panel. Look for ground on pin 16 (white/black). If you don't have ground on pin 16 gain access to J/B 3 and do a continuity test.

I suspect something in J/B 3 has gone bad or the ground on IG has come loose.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.